Summa Theologiae I-II, QQ. 109, 112: Grace

Objection 1. It seems that without grace man can know no truth. For, on 1 Cor. xii. 3: No man can say, the Lord Jesus, but by the Holy Ghost, the gloss says: Every truth, by whomsoever spoken is from the Holy Ghost. Now the Holy Ghost dwells in us by grace. Therefore we cannot know truth without grace.

Scripture: 1Cor 12:3

Obj. 2. Further, Augustine says (Solil. i.) that the most certain sciences are like things lit up by the sun so as to be seen. Now God Himself is He Who sheds the light. And reason is in the mind as sight is in the eye. And the eyes of the mind are the senses of the soul. Now the bodily senses, however pure, cannot see any visible object, without the sun's light. Therefore the human mind, however perfect, cannot, by reasoning, know any truth without Divine light: and this pertains to the aid of grace.

Obj. 3. Further, the human mind can only understand truth by thinking, as is clear from Augustine (De Trin. xiv.). But the Apostle says (2 Cor. iii. 5): Not that we are sufficient to think anything of ourselves, as of ourselves; but our sufficiency is from God. Therefore man cannot, of himself, know truth without the help of grace.

Scripture: 2Cor 3:5

On the contrary, Augustine says (Retract. i.): I do not approve having said in the prayer, O God, Who dost wish the sinless alone to know the truth; for it may be answered that many who are not sinless know many truths. Now man is cleansed from sin by grace, according to Ps. l. 12: Create a clean heart in me, O God, and renew a right spirit within my bowels. Therefore without grace man of himself can know truth.

Scripture: Ps 51:10

I answer that, To know truth is a use or act of intellectual light, since, according to the Apostle (Eph. v. 13): All that is made manifest is light. Now every use implies movement, taking movement broadly, so as to call thinking and willing movements, as is clear from the Philosopher (De Anima, iii.). Now in corporeal things we see that for movement there is required not merely the form which is the principle of the movement or action, but there is also required the motion of the first mover. Now the first mover in the order of corporeal things is the heavenly body. Hence no matter how perfectly fire has heat, it would not bring about alteration, except by the motion of the heavenly body. But it is clear that as all corporeal movements are reduced to the motion of the heavenly body as to the first corporeal mover, so all movements, both corporeal and spiritual, are reduced to the simple First Mover, Who is God. And hence no matter how perfect a corporeal or spiritual nature is supposed to be, it cannot proceed to its act unless it be moved by God; but this motion is according to the plan of His providence, and not by a necessity of nature, as the motion of the heavenly body. Now not only is every motion from God as from the First Mover, but all formal perfection is from Him as from the First Act. And thus the act of the intellect or of any created being whatsoever depends upon God in two ways: first, inasmuch as it is from Him that it has the form whereby it acts; secondly, inasmuch as it is moved by Him to act.

Now every form bestowed on created things by God has power for a determined act, which it can bring about in proportion to its own proper endowment; and beyond which it is powerless, except by a superadded form, as water can only heat when heated by the fire. And thus the human understanding has a form, viz., intelligible light, which of itself is sufficient for knowing certain intelligible things, viz., those we can come to know through the senses. Higher intelligible things the human intellect cannot know, unless it be perfected by a stronger light, viz., the light of faith or prophecy which is called the light of grace, inasmuch as it is added to nature.

Hence we must say that for the knowledge of any truth whatsoever man needs Divine help, that the intellect may be moved by God to its act. But he does not need a new light added to his natural light, in order to know the truth in all things, but only in some that surpass his natural knowledge. And yet at times God miraculously instructs some by His grace in things that can be known by natural reason, even as He sometimes brings about miraculously what nature can do.

Scripture: Eph 5:13

Reply Obj. 1. Every truth by whomsoever spoken is from the Holy Ghost as bestowing the natural light, and moving us to understand and speak the truth, but not as dwelling in us by sanctifying grace, or as bestowing any habitual gift superadded to nature. For this only takes place with regard to certain truths that are known and spoken, and especially in regard to such as pertain to faith, of which the Apostle speaks.

Reply Obj. 2. The material sun sheds its light outside us; but the intelligible Sun, Who is God, shines within us. Hence the natural light bestowed upon the soul is God's enlightenment, whereby we are enlightened to see what pertains to natural knowledge; and for this there is required no further knowledge, but only for such things as surpass natural knowledge.

Reply Obj. 3. We always need God's help for every thought, inasmuch as He moves the understanding to act; for actually to understand anything is to think, as is clear from Augustine (De Trin. xiv.).

Objection 1. It seems that man can wish and do good without grace. For that is in man's power, whereof he is master. Now man is master of his acts, and especially of his willing, as stated above (Q. I., A. 1; Q. XIII., A. 6). Hence man, of himself, can wish and do good without the help of grace.

Obj. 2. Further, man has more power over what is according to his nature than over what is beyond his nature. Now sin is against his nature, as Damascene says (De Fide Orthod. ii.); whereas deeds of virtue are according to his nature, as stated above (Q. LXXI., A. 1). Therefore since man can sin of himself, much more would it seem that of himself he can wish and do good.

Obj. 3. Further, the understanding's good is truth, as the Philosopher says (Ethic. vi.). Now the intellect can of itself know truth, even as every other thing can work its own operation of itself. Therefore, much more can man, of himself, do and wish good.

On the contrary, The Apostle says (Rom. ix. 16): It is not of him that willeth (i.e., to will), nor of him that runneth (i.e., to run), but of God that showeth mercy. And Augustine says (De Corrept. et Gratia, ii.) that without grace men do nothing good when they either think or wish or love or act.

Scripture: Rom 9:16

I answer that, Man's nature may be looked at in two ways: first, in its integrity, as it was in our first parent before sin; secondly, as it is corrupted in us after the sin of our first parent. Now in both states human nature needs the help of God as First Mover, to do or wish any good whatsoever, as stated above (A. 1). But in the state of integrity, as regards the sufficiency of the operative power, man by his natural endowments could wish and do the good proportionate to his nature, such as the good of acquired virtue; but not surpassing good, as the good of infused virtue. But in the state of corrupt nature, man falls short of what he could do by his nature, so that he is unable to fulfil it by his own natural powers. Yet because human nature is not altogether corrupted by sin, so as to be shorn of every natural good, even in the state of corrupted nature it can, by virtue of its natural endowments, work some particular good, as to build dwellings, plant vineyards, and the like; yet it cannot do all the good natural to it, so as to fall short in nothing; just as a sick man can of himself make some movements, yet he cannot be perfectly moved with the movements of one in health, unless by the help of medicine he be cured.

And thus in the state of perfect nature man needs a gratuitous strength superadded to natural strength for one reason, viz., in order to do and wish supernatural good; but for two reasons, in the state of corrupt nature, viz., in order to be healed, and furthermore in order to carry out works of supernatural virtue, which are meritorious. Beyond this, in both states man needs the Divine help, that he may be moved to act well.

Reply Obj. 1. Man is master of his acts and of his willing or not willing, because of his deliberate reason, which can be bent to one side or another. And although he is master of his deliberating or not deliberating, yet this can only be by a previous deliberation; and since it cannot go on to infinity, we must come at length to this, that man's free-will is moved by an extrinsic principle, which is above the human mind, to wit by God, as the Philosopher proves in a chapter on Good Fortune (Ethic. Eudem. vii.). Hence the mind of man still unweakened is not so much master of its act that it does not need to be moved by God; and much more the free-will of man weakened by sin, whereby it is hindered from good by the corruption of the nature.

Reply Obj. 2. To sin is nothing else than to fail in the good which belongs to any being according to its nature. Now as every created thing has its being from another, and, considered in itself, is nothing, so does it need to be preserved by another in the good which pertains to its nature. For it can of itself fail in good, even as of itself it can fall into non-existence, unless it is upheld by God.

Reply Obj. 3. Man cannot even know truth without Divine help, as stated above (A. 1). And yet human nature is more corrupt by sin in regard to the desire for good, than in regard to the knowledge of truth.

Objection 1. It seems that without grace man cannot love God above all things by his own natural powers. For to love God above all things is the proper and principal act of charity. Now man cannot of himself possess charity, since the charity of God is poured forth in our hearts by the Holy Ghost Who is given to us, as is said Rom. v. 5. Therefore man by his natural powers alone cannot love God above all things.

Scripture: Rom 5:5

Obj. 2. Further, no nature can rise above itself. But to love God above all things is to tend above oneself. Therefore without the help of grace no created nature can love God above itself.

Obj. 3. Further, to God, Who is the Highest Good, is due the best love, which is that He be loved above all things. Now without grace man is not capable of giving God the best love, which is His due; otherwise it would be useless to add grace. Hence man, without grace and with his natural powers alone, cannot love God above all things.

On the contrary, As some maintain, man was first made with only natural endowments; and in this state it is manifest that he loved God to some extent. But he did not love God equally with himself, or less than himself, otherwise he would have sinned. Therefore he loved God above himself. Therefore man, by his natural powers alone, can love God more than himself and above all things.

I answer that, As was said above (P. i., Q. LX., A. 5), where the various opinions concerning the natural love of the angels were set forth, man in a state of perfect nature, could by his natural power, do the good natural to him without the addition of any gratuitous gift, though not without the help of God moving him. Now to love God above all things is natural to man and to every nature, not only rational but irrational, and even to inanimate nature according to the manner of love which can belong to each creature. And the reason of this is that it is natural to all to seek and love things according as they are naturally fit (to be sought and loved) since all things act according as they are naturally fit as stated in Phys. ii. Now it is manifest that the good of the part is for the good of the whole; hence everything, by its natural appetite and love, loves its own proper good on account of the common good of the whole universe, which is God. Hence Dionysius says (Div. Nom. iv.) that God leads everything to love of Himself. Hence in the state of perfect nature man referred the love of himself and of all other things to the love of God as to its end; and thus he loved God more than himself and above all things. But in the state of corrupt nature man falls short of this in the appetite of his rational will, which, unless it is cured by God's grace, follows its private good, on account of the corruption of nature. And hence we must say that in the state of perfect nature man did not need the gift of grace added to his natural endowments, in order to love God above all things naturally, although he needed God's help to move him to it; but in the state of corrupt nature man needs, even for this, the help of grace to heal his nature.

Reply Obj. 1. Charity loves God above all things in a higher way than nature does. For nature loves God above all things inasmuch as He is the beginning and the end of natural good; whereas charity loves Him, as He is the object of beatitude, and inasmuch as man has a spiritual fellowship with God. Moreover charity adds to natural love of God a certain quickness and joy, in the same way that every habit of virtue adds to the good act which is done merely by the natural reason of a man who has not the habit of virtue.

Reply Obj. 2. When it is said that nature cannot rise above itself, we must not understand this as if it could not be drawn to any object above itself, for it is clear that our intellect by its natural knowledge can know things above itself, as is shown in our natural knowledge of God. But we are to understand that nature cannot rise to an act exceeding the proportion of its strength. Now to love God above all things is not such an act; for it is natural to every creature, as was said above.

Reply Obj. 3. Love is said to be best, both with respect to the degree of love, and with regard to the motive of loving, and the mode of love. And thus the highest degree of love is that whereby charity loves God as the giver of beatitude, as was said above.

Objection 1. It seems that man without grace, and by his own natural powers, can fulfil the commandments of the Law. For the Apostle says (Rom. ii. 14) that the Gentiles who have not the law, do by nature those things that are of the Law. Now what a man does naturally he can do of himself without grace. Hence a man can fulfil the commandments of the Law without grace.

Scripture: Rom 2:14

Obj. 2. Further, Jerome (Pelagius) says in his Exposition of the Catholic Faith that they are anathema who say God has laid impossibilities upon man. Now what a man cannot fulfil by himself is impossible to him. Therefore a man can fulfil all the commandments of himself.

Obj. 3. Further, of all the commandments of the Law, the greatest is this. Thou shalt love the Lord thy God with thy whole heart (Matth. xxii. 37). Now man with his natural endowments can fulfil this command by loving God above all things, as stated above (A. 3). Therefore man can fulfil all the commandments of the Law without grace.

Scripture: Matt 22:37

On the contrary, Augustine says (De Hæres. lxxxviii.) that it is part of the Pelagian heresy that they believe that without grace man can fulfil all the Divine commandments.

I answer that, There are two ways of fulfilling the commandments of the Law.—The first regards the substance of the works, as when a man does works of justice, fortitude, and of other virtues. And in this way man in the state of perfect nature could fulfil all the commandments of the Law; otherwise he would have been unable to sin in that state, since to sin is nothing else than to transgress the Divine commandments. But in the state of corrupted nature man cannot fulfil all the Divine commandments without healing grace. Secondly, the commandments of the law can be fulfilled not merely as regards the substance of the act, but also as regards the mode of acting, i.e., their being done out of charity. And in this way, neither in the state of perfect nature, nor in the state of corrupt nature can man fulfil the commandments of the law without grace. Hence, Augustine (De Corrept. et Grat. ii.) having stated that without grace men can do no good whatever, adds: Not only do they know by its light what to do, but by its help they do lovingly what they know. Beyond this, in both states they need the help of God's motion in order to fulfil the commandments, as stated above (AA. 2, 3).

Reply Obj. 1. As Augustine says (De Spir. et Lit. xxvii.), do not be disturbed at his saying that they do by nature those things that are of the Law; for the Spirit of grace works this, in order to restore in us the image of God, after which we were naturally made.

Reply Obj. 2. What we can do with the Divine assistance is not altogether impossible to us; according to the Philosopher (Ethic. iii.): What we can do through our friends, we can do, in some sense, by ourselves. Hence Jerome (Pelagius) concedes (ibid.) that our will is in such a way free that we must confess we still require God's help.

Reply Obj. 3. Man cannot, with his purely natural endowments, fulfil the precept of the love of God, as stated above (A. 3).

Objection 1. It seems that man can know that he has grace. For grace by its physical reality is in the soul. Now the soul has most certain knowledge of those things that are in it by their physical reality, as appears from Augustine (Gen. ad lit. xii.). Hence grace may be known most certainly by one who has grace.

Obj. 2. Further, as knowledge is a gift of God, so is grace. But whoever receives knowledge from God, knows that he has knowledge, according to Wis. vii. 17: The Lord hath given me the true knowledge of the things that are. Hence, with equal reason, whoever receives grace from God, knows that he has grace.

Obj. 3. Further, light is more knowable than darkness, since, according to the Apostle (Eph. v. 13), all that is made manifest is light. Now sin, which is spiritual darkness, may be known with certainty by one that is in sin. Much more, therefore, may grace, which is spiritual light, be known.

Scripture: Eph 5:13

Obj. 4. Further, the Apostle says (1 Cor. ii. 12): Now we have received not the Spirit of this world, but the Spirit that is of God; that we may know the things that are given us from God. Now grace is God's first gift. Hence, the man who receives grace by the Holy Spirit, by the same Holy Spirit knows the grace given to him.

Scripture: 1Cor 2:12

Obj. 5. Further, it was said by the Lord to Abraham (Gen. xxii. 12): Now I know that thou fearest God, i.e., I have made thee know. Now He is speaking there of chaste fear, which is not apart from grace. Hence a man may know that he has grace.

Scripture: Gen 22:12

On the contrary, It is written (Eccles. ix. 1): Man knoweth not whether he be worthy of love or hatred. Now sanctifying grace maketh a man worthy of God's love. Therefore no one can know whether he has sanctifying grace.

Scripture: Eccl 9:1

I answer that, There are three ways of knowing a thing:—First, by revelation, and thus anyone may know that he has grace, for God by a special privilege reveals this at times to some, in order that the joy of safety may begin in them even in this life, and that they may carry on toilsome works with greater trust and greater energy, and may bear the evils of this present life, as when it was said to Paul (2 Cor. xii. 9): My grace is sufficient for thee.

Secondly, a man may, of himself, know something, and with certainty; and in this way no one can know that he has grace. For certitude about a thing can only be had when we may judge of it by its proper principle. Thus it is by undemonstrable universal principles that certitude is obtained concerning demonstrative conclusions. Now no one can know he has the knowledge of a conclusion if he does not know its principle. But the principle of grace and its object is God, Who by reason of His very excellence is unknown to us, according to Job xxxvi. 26. Behold God is great, exceeding our knowledge. And hence His presence in us and His absence cannot be known with certainty, according to Job ix. 11: If He come to me, I shall not see Him; if He depart I shall not understand. And hence man cannot judge with certainty that he has grace, according to 1 Cor. iv. 3, 4: But neither do I judge my own self... but He that judgeth me is the Lord.

Thirdly, things are known conjecturally by signs; and thus anyone may know he has grace, when he is conscious of delighting in God, and of despising worldly things, and inasmuch as a man is not conscious of any mortal sin. And thus it is written (Apoc. ii. 17): To him that overcometh I will give the hidden manna... which no man knoweth, but he that receiveth it, because whoever receives it knows, by experiencing a certain sweetness, which he who does not receive it, does not experience. Yet this knowledge is imperfect; hence the Apostle says (1 Cor. iv. 4): I am not conscious to myself of anything, yet am I not hereby justified, since, according to Ps. xviii. 13: Who can understand sins? From my secret ones cleanse me, O Lord, and from those of others spare Thy servant.

Scripture: 2Cor 12:9, Job 36:26, Job 9:11, 1Cor 4:3-4, Rev 2:17, 1Cor 4:4, Ps 19:12

Reply Obj. 1. Those things which are in the soul by their physical reality, are known through experimental knowledge; in so far as through acts man has experience of their inward principles: thus when we wish, we perceive that we have a will; and when we exercise the functions of life, we observe that there is life in us.

Reply Obj. 2. It is an essential condition of knowledge that a man should have certitude of the objects of knowledge; and again, it is an essential condition of faith that a man should be certain of the things of faith, and this, because certitude belongs to the perfection of the intellect, wherein these gifts exist. Hence, whoever has knowledge or faith is certain that he has them. But it is otherwise with grace and charity and suchlike, which perfect the appetitive faculty.

Reply Obj. 3. Sin has for its principal object commutable good, which is known to us. But the object or end of grace is unknown to us on account of the greatness of its light, according to 1 Tim. vi. 16: Who... inhabiteth light inaccessible.

Scripture: 1Tim 6:16

Reply Obj. 4. The Apostle is here speaking of the gifts of glory, which have been given to us in hope, and these we know most certainly by faith, although we do not know for certain that we have grace to enable us to merit them.—Or it may be said that he is speaking of the privileged knowledge, which comes of revelation. Hence he adds (verse 10): But to us God hath revealed them by His Spirit.

Reply Obj. 5. What was said to Abraham may refer to experimental knowledge which springs from deeds of which we are cognizant. For in the deed that Abraham had just wrought, he could know experimentally that he had the fear of God.—Or it may refer to a revelation.